This invention relates to a numerical control system, and more particularly to a numerical control system which enables both a machine tool and a robot to be controlled by a single numerical control device.
Numerical control systems often comprise a numerical control device, a machine tool, which is controlled by the numerical control device so as to machine a workpiece, and a robot for mounting workpieces on the machine tool and demounting the workpieces from the machine tool, for exchanging tools, for cleaning scraps produced by the machining operation, and for various other tasks. Ordinarily, such numerical control systems are separate, with a robot control device exclusively for controlling the robot. The robot control device causes the robot to execute the above tasks by controlling the vertical movement of the robot arm, the swinging motion of the arm to the left and right, the rotation of a wrist, the shaking of a hand mechanism, the opening and closing of fingers provided on the hand mechanism, and the like. The robot control device also controls editing, such as the deletion and correction of robot command data, as well as the teaching of robot command data. The device is therefore composed of large quantities of hardware such as a processing circuit, a memory and a pulse distributing circuit, which raise the cost of the device and, hence, the cost of the overall system. This has impeded the wider use of robot systems.
It should be noted, however, that the hardware, such as the processing circuit, memory and pulse distributing circuit, which is necessary for a robot control device is almost entirely incorporated in the conventional numerical control devices. Thus, it should be possible to greatly reduce the cost of an overall system if a numerical control device could be furnished with the function of the robot control device by the addition of a minimum amount of necessary hardware.